Yobi which terminal are you using at Heathrow? I can post the number for you - give them a call, I've always found them really helpful. They have held items for me in the past too
Just thinking though, when you fly from London to Paris, you might be using Terminal 1 or 4? BA use T4, British Midland use T1, and Air France use T2. Just gotta hope you're flying British Airways or British Midland!
I need to stop flying from Terminal 3 and use BA at Terminal 4 instead. Chanel, Mulberry and Hermes. Who cares about Eurobonus points when you can get things taxfree